Preheat oven to 170 degrees.
Grease the baking dish. It is recommended to use a form with a depth of 5 cm and a volume of 1.5 liters, but I had 2 forms of smaller size and volume.
Using a mixer, beat butter, sugar, zest and yolks...
... until the mass thickens and brightens.
Sift flour with baking powder on top and gently stir it with a metal spoon.
Gently stir the juice...
... and milk.
Beat the whites to soft peaks.
Transfer the mixture to a baking dish. Put in a large-sized form, pour in enough hot water to get up to half of the pudding.
Bake 50-55 minutes until Golden brown.
Sprinkle with powdered sugar. Let stand for 5 minutes before serving.Dessert turns of three layers: the bottom layer of dough, tender cream, and the top is foamy crust. This is surprising, given that we mixed all the ingredients in one container.